I would just recommend activating it AFTER the balance mods.
Heck no, install and activate Barbarians!
before any other compatible gameplay mods, like Thal's Combined!
Otherwise, all those scripted unit-class changes of a balance mod, like Thal's, won't affect the new added standard units of Barbarians!.
That's at least how I understand the way mod installation works.
Bismarck players could possibly end up with stronger or weaker converted vanilla units than other nations if those added units are installed afterwards.
I stick to the vanilla stats because I assume more or less everyone is going to play with a big balance mod anyway.
Of course, Barbarians! is a balance mod because it gives the poor Barbarians a better chance to survive against those other arrogant civilizations.
Well, you may copy whatever you need from Barbarians! but like mentioned here, this is just a little addon-mod of mine everyone can decide for oneself if a barbarian challenge is wanted or not.